In particular, just as in the large volume scattering diagram
of [1]}, the initial rays associated to \(\mathcal {O}(m)\)  and \(\mathcal {O}(m)[1]\)  are straight
lines tangent to the parabola \(y=-\frac{1}{2} x^2\)  at \(x=m\) , but their starting point is
displaced by a horizontal distance \(\mathcal {V}_\psi \mathcal {V}\tan \psi \)  along that tangent.
<FIGURE><FIGURE>